Dimensional Transfer Research Articles

Design and optimization of three dimensional multi-load wireless transfer system

Design and optimization of three dimensional multi-load wireless transfer system

Self-assembly synthesis of two dimensional vanadium oxide nanotriangles for photocatalytic application

For the first time, we report a Two Dimensional Phase Transfer Reaction (2DPTR) between the three different phases of 2D nanosheets and their applications in catalysis and hydrogen evolution. Plasmonic two-dimensional (2D) nanomaterials have created a niche for themselves in a variety of applications due to their unique and tunable optical properties. In the present work, we report a simple method for the synthesis of three different phases of the 2D vanadium oxide nanosheets to convert to each other at room temperature (amorphous, nanoflakes and nanotriangles). We developed a two-step method that first involves probe ultrasonication to mediate the synthesis of 2D vanadium oxide nanoflakes (VNFs) at room temperature and secondly, their phase transformation to VNTs using hydrogen peroxide or Isopropyl Alcohol (IPA) as the phase transfer reagents. 2D VNTs have been studied for morphological, structural, and optical properties by using a variety of instruments, including TEM, UV–Vis, EPR, RAMAN, and XPS. Thus, after treatment with hydrochloric acid (HCl), the 2D vanadium oxide nanoflakes are easily converted to the 2D amorphous nanosheets (Vam) which then regain crystallinity in the form of VNTs after the addition of Hydrogen peroxide or IPA, with a plasmonic peak around 450 nm. Oxygen vacancies are created in the VNFs, after treatment with HCl, which results in the crystal lattice breakdown. These oxygen vacancies were filled up again when the nanoflakes were treated with hydrogen peroxide or IPA and then resulted in the formation of VNTs. The UV–vis spectroscopy was performed with different addition of concentrations of H2O2, the limit of detection 34.1 µM and linear range 0 to 1000 µM found. Also, a selectivity study proved H2O2 in these 2D VNTs. Vam and VNT also showed effective photocatalytic activity against KMnO4 which is a strong oxidizing reagent used in water treatment. The synthesis and plasmonic nature of the 2D VNTs and the photocatalytic activity of Vam and VNT present in this study is a pioneer report for these novel 2D nanomaterials and they can be further explored with many possibilities in many fields including sensing, catalysis, energy, biomedicine, and many other significant applications in the near future.

Cross-dimensional transfer learning in medical image segmentation with deep learning.

Over the last decade, convolutional neural networks have emerged and advanced the state-of-the-art in various image analysis and computer vision applications. The performance of 2D image classification networks is constantly improving and being trained on databases made of millions of natural images. Conversely, in the field of medical image analysis, the progress is also remarkable but has mainly slowed down due to the relative lack of annotated data and besides, the inherent constraints related to the acquisition process. These limitations are even more pronounced given the volumetry of medical imaging data. In this paper, we introduce an efficient way to transfer the efficiency of a 2D classification network trained on natural images to 2D, 3D uni- and multi-modal medical image segmentation applications. In this direction, we designed novel architectures based on two key principles: weight transfer by embedding a 2D pre-trained encoder into a higher dimensional U-Net, and dimensional transfer by expanding a 2D segmentation network into a higher dimension one. The proposed networks were tested on benchmarks comprising different modalities: MR, CT, and ultrasound images. Our 2D network ranked first on the CAMUS challenge dedicated to echo-cardiographic data segmentation and surpassed the state-of-the-art. Regarding 2D/3D MR and CT abdominal images from the CHAOS challenge, our approach largely outperformed the other 2D-based methods described in the challenge paper on Dice, RAVD, ASSD, and MSSD scores and ranked third on the online evaluation platform. Our 3D network applied to the BraTS 2022 competition also achieved promising results, reaching an average Dice score of 91.69% (91.22%) for the whole tumor, 83.23% (84.77%) for the tumor core and 81.75% (83.88%) for enhanced tumor using the approach based on weight (dimensional) transfer. Experimental and qualitative results illustrate the effectiveness of our methods for multi-dimensional medical image segmentation.

Perceptual integrality of foreign segmental and tonal information: Dimensional transfer hypothesis

AbstractThis study investigates whether (a) Cantonese and (b) English listeners integrally or independently perceive Thai tone and segmental information. Listeners completed a modified AX discrimination task that contained a control block (without segmental variation) and an orthogonal block (with segmental variation). Relative to their own performance in the control block, the Cantonese listeners showed increased response time, decreased proportion of accuracy, and decreased sensitivity index in the orthogonal block. By contrast, the English listeners showed similar response time, proportion of accuracy, and sensitivity index across the two blocks. These reflect integral processing among the Cantonese but not the English listeners. This finding motivates the dimensional transfer hypothesis. The hypothesis posits that L1 perceptual experience shapes the perceptual integrality (or nonintegrality) of foreign suprasegmental and segmental information.

External and Internal Reliability of Digital Indirect Bonding Technique Using Three Dimensional Models and Double Transfer Trays

Introduction: Digital technology invaded all branches of orthodontics such as diagnostic aids, treatment planning, manufacturing of appliances and printing 3D models. there were many CAD programs to facilitate bracket placement more precisely and efficiently. there were many studies evaluated the efficacy and precision of digital indirect bonding approach and they found that it is effective strategy in general. However, there were limited research on the external reliability of digital indirect bonding approaches in literatures. Aim of the Study: To evaluate digitally the amount of discrepancy happened in bracket positions during transferring them by indirect bonding tray inside the patient’s mouth and external reliability of the measurements. Materials and Methods: Ten patients (4 males and 6 females), ranging from 15.9 to 23.4 years of age (mean 19.647 years, SD± 2.232), PVS impressions was taken for the upper arch of the patients and scanned by laboratory scanner to produce STL files to create digital models. digital indirect bonding of 100 American Orthodontic minimaster braces were performed on upper arch by positioning brackets on digital models using Ortho Analyzer (3Shape) software. Then, printing 3D model with braces and constructing the double transfer tray to be loaded with braces to bond it inside the patient’s mouth. After that, scanning of the bonded brackets was done by CEREC omnicam. Geomagic Control X software was used to measure the deviations happened in the bracket position on the patient’s mouth and the bracket position in Orthoanalyzer (3Shape) software. Results: Overall linear measurements were ranging from (-173.1±131.65 μm) to (200.2±132.86 μm). These deviations were related to occlusogingival and in-out directions and denoted to upper right first premolars and upper left canines respectively. Overall angular measurements were ranging from (0.51±0.03 degree) to (1.94±0.03 degree). These deviations were related to mesiodistal tip and denoted to upper right canines and upper left central incisors respectively. Discussion: The overall angular differences in the present study ranged from 0.51° to 1.94° and overall linear differences ranged from 0.1731 mm to 0.2002 mm, which agreed with those observed in the literature, confirming the reliability of the technique. Conclusion: Indirect bonding with a dual transfer tray can correctly replicate the position of brackets on digital models.

Detection on the coating peeling of SiC coated C/C composites using infrared thermal-wave tomography

The coating damage of SiC-coated carbon–carbon (C/C) composite is directly influenced on the anti-oxidation attack and ablation performances of carbon–carbon (C/C) composite substrate. It is unprecedentedly reported that infrared thermal-wave tomography (IR-TWT or TWT) approach with laser as external stimulation source is successfully employed for the evaluation of the SiC damage coated on the C/C composite substrate. The stimulation laser intensity is varied according to a chirp-pulsed chain, and employed to induce the chirp-pulsed radar thermal-wave signal. The thermal-wave signals of SiC-coated C/C composite dependence on coating thickness degradation and substrate material are deeply analyzed by using of one dimensional (1D) thermal-wave transfer analytical model. A temporal amplitude of thermal-wave signal as function of delay time is obtained by using of dual-orthogonal demodulation (DOD) algorithms, and it can be employed to represent thermal-wave transmission and to perform tomography. Experimental results confirm that TWT can be used to accurately and reliably assess the SiC coating damage characterization from the C/C composite substrate.

Organic Electron Donor‐Acceptor Co‐intercalated NiMn‐LDHs – Photocatalysts with Enhanced Separation of Charge Carriers for Photocatalytic Reduction of CO2

AbstractDeveloping good photocatalysts for reducing CO2 to carbonaceous fuels has aroused interest. However, the efficiency of photocatalytic CO2 reduction remains low. In this work, we report a novel organic electron donor‐acceptor system to realize the two dimensional photoinduced electron transfer (PET) process by coprecipitation‐in situ oxidation method to synthesize 4,4′‐diaminostilbene‐2,2′‐disulfonic acid (DAS) and 4,4′‐dinitrostilbene‐2,2′‐disulfonic acid disodium salt (DNS) co‐intercalated Ni2Mn‐LDHs (Ni2Mn‐LDHs‐DAS, DNS). Due to the two‐dimensional confinement of LDHs, DAS and DNS were arranged in a single molecule parallel in the interlayer, resulting in a π‐π interaction between the two organic anions. It promoted the photogenerated electrons by the DAS‐DNS to migrate to the hydrotalcite layer to participate in CO2 photoreduction rather than recombination with the holes. The optimum Ni2Mn‐DAS, DNS‐n showed the highest total consumed electron number of 13.99 μmol g−1, which was 3 times higher than that of Ni2Mn−CO3. Our findings provide a new way for improving the CO2 photoreduction activity of hydrotalcite‐based photocatalysts and achieve the combination of organic and inorganic semiconductors.

Ageing of pipe induced chlorine concentration decay: A one dimensional mass transfer modeling

We report here the one-dimensional mass transfer equation for modeling of chlorine decay process in water distribution system. Furthermore, Arrhenius model was augmented with unsteady state mass transport and ageing factor due to wall reaction. A detailed analysis of flow velocities, temperatures and ageing factors are compared. The results show that chlorine decay strongly depends on slow velocities, temperature and high wall reaction coefficient of aged pipe. The chlorine decays gradually at lower temperature up to 20 °C but a sharp increase was found with the increase in temperature.

The Effect of Thermal Radiation on the Surface Catalytic Chemical Reaction

The effect of thermal radiation on the two - dimensional, steady-state, coupled heat and mass transfer from a fluid flow to a sphere in the presence of an exothermal catalytic chemical reaction on the surface of the sphere is investigated in the present work. The P1 approximation models the radiative transfer. The finite difference method was used to discretize the mathematical model equations. The discrete equations were solved by the defect correction - multigrid method. The influence of thermal radiation on the sphere surface temperature, concentration and reaction rate was analysed. It was found that, for high values of the radiation conduction parameter, thermal radiation has a significant effect on the surface reaction.

Studies on the performance of 150W solar photovoltaic module with evaporative cooling

The increase in surface temperature of solar photovoltaic module due to incident solar radiation has an adverse impact on its performance, reducing its electrical output power and efficiency. Proper cooling can improve the electrical efficiency, and decrease the rate of cell degradation with time, resulting in maximization of life span of photovoltaic modules. Various methods like active cooling, passive cooling and heat pipe cooling are employed to cool the module. In the present work, water passive cooling technique has been used since this method is preferred for small modules and is more efficient because of higher thermal capacity of water. Evaporative cooling is one such technique. Numerical and experimental investigations have been carried out to study the effect of evaporative cooling on the performance of solar photovoltaic module. A two dimensional, steady state, cross flow, heat and mass transfer model has been developed and temperature distribution of air and water across a cooling pad has been studied. An evaporative cooling pad is incorporated at the bottom surface of solar photovoltaic module. Experiments are conducted to evaluate the performance of solar PV module and the results are compared with that of numerical simulation.

Heat transfer optimization through new form of pin type of finned tube heat exchangers using the exergy and energy analysis

Abstract In the present work, computational fluid dynamics method is used to simulate the three dimensional turbulent thermal energy transfer and fluid flow through the new types of the finned tube heat exchangers. The realizable turbulent kinetic energy - turbulent kinetic energy dissipation model is selected as the turbulence model because it has the best results compared to the other turbulence models with the experimental data. After the simulation the energy and exergy analysis are performed and a multi-objective model is defined to obtain the optimal and critical values of the operational and geometrical parameters. Furthermore, equations are suggested for estimation the three objective parameters i.e. thermal effectiveness, dimensionless exergy loss and dimensionless work. Results also indicate, the dimensionless exergy loss is optimum at Re=8333 and Pr=10.63. Furthermore, it was found, the optimum value for the transverse pitch is equal to 3.52, when the objective parameters are the thermal effectiveness and the dimensionless exergy loss.

Dimension-Tunable Circularly Polarized Luminescent Nanoassemblies with Emerging Selective Chirality and Energy Transfer.

The selective interplay between dimensional morphology transition and signal transfer is an important feature for both nanomaterials and biosystems. While most of those reported examples considered either dimensional transition or signal transfer, the integrated interplay or selectivity for these two aspects in single self-assembled system has been rarely studied. Here, we report that a positively charged chiral π-building block could self-assemble into multidimensional nanostructures, which showed tunable circularly polarized luminescence (CPL). Impressively, when these CPL-active multidimensional structures interacted with two achiral dyes (positively charged ThT and negatively charged CNA), 3D nanocubes and 0D nanospheres showed neither chirality transfer nor energy transfer, while 2D nanoplates could successfully trigger a selective chirality or energy transfer depending on the charge type of acceptor dyes, which then emitted an enhanced CPL signal. This work demonstrated rational design of charged π-building block for the construction of dimension controllable and selective signal transfer self-assembly system, which might deepen the understanding the interplay of dimensional structures and signal transfer functions in natural and nano systems.

One Dimensional Mass Transfer Effects on Transient Free Convection Flow with Vertical Porous Plate

The aspiration of the mechanism is the impacts of radiation and mass transfer on the transient free convection flow of a dissipative fluid with the vertical Porous plate by taking into a consideration of the viscous dissipation. The governing equations for the one-dimensional model are solved with proper boundary conditions. The radiative heat transfer in the limit of the optically thick fluid is described. The momentum coupled equation with the energy and mass diffusion equations are solved by explicit finite difference method (EFDM). For Tran programming language is used as the main tool for calculating the simulating results. A parametric evaluation displaying the influence of distinct flow parameters on velocity profile, transient temperature and concentration are outlined graphically with the help of tecplot-9. Finally, a comparison of the present study with the previous study has been deliberated for different interesting parameters.

Vertically aligned nanostructured FeOOH@MnO2 core shell electrode with better areal capacitance

Present work focuses on hydrothermal preparation of FeOOH@MnO2 core shell as a vertically aligned 1-D nanostructure and improvement in electrochemical charge storage by utilizing MnO2 nanostructure as an active electrode material and vertically aligned FeOOH nanorods for one dimensional electron transfer paths. A FeOOH@MnO2 core shell thin film electrode gives maximum capacitance of 0.252 Fcm−2 for the applied current density of 1 mAcm−2 and maintains 99.5% capacitance retention for 2000 charge discharge cycles at 5 mAcm−2 that attributes to better capacitive charge storage in the material. Assembled solid state symmetric electrochemical capacitor of FeOOH@MnO2 electrode yields maximum of 0.05 mWhcm−2 energy density with power delivery of 1.5 mWcm−2.

Non-contrast enhanced molecular characterization of C6 rat glioma tumor at 7 T

PurposeThe aim of this study was to investigate, how to assess the relevant magnetization changes in the rat brain tissue due to the present of glioma tumor and its growth at a 7 T animal magnetic resonance imaging (MRI) system. Material and methodsFor this study, a custom-built two dimensional (2D) chemical exchange saturation transfer (CEST) pulse sequence was optimized for different tissue properties using fresh and cooked quail eggs. C6 tumor cells were investigated by in-vivo and post-mortem measurements in six Wistar rats using the optimized CEST sequence up to 5 weeks. Magnetization transfer ratio (MTR)- and asymmetric MTR (MTRasym)-maps of rat brains were created at different frequency offsets. In-vivo results were verified by 1H spectroscopic, histological and also in-vitro C6 cell culture examinations. ResultsThe CEST module for the optimal visualization of magnetization effects consists of five RF-pulses, each with a duration of 20 ms and a flip angle of 180°. In-vivo and post-mortem z-spectra of the cerebrospinal fluid (CSF), cortex, myelinated/demyelinated, healthy and tumorous tissue and tumor rim were obtained. The magnetization level and shape of the z-spectra on the upfield and downfield from the water peak were not the same. The magnetization dips on the upfield and downfield from the water peak of the z-spectra disappeared due to the thermal denaturation in cooked quail eggs and due to formaldehyde-induced fixation in post-mortem rat brains. The z-spectra of the rat brain in a range of ±2 to ±4 ppm displayed valuable information about the differentiation of various brain regions from the tumor tissue. Histological examinations confirmed our results. The C6 cell culture examinations showed that the observed magnetization changes in the rat brain occurred only due to the interaction between glioma cells and their environment in the rat brain and not from the C6 tumor cells. ConclusionsBased on our in-vivo and post-mortem results, it is to be recommended to create the MTR-maps at a special offset frequency depending on the aim of research project instead of MTRasym-maps. Otherwise, the desired effect attenuates or vanishes.

N/S co-doped 3D carbon framework prepared by a facile morphology-controlled solid-state pyrolysis method for oxygen reduction reaction in both acidic and alkaline media

Abstract Developing high-performance non-precious metal electrocatalysts for oxygen reduction reaction (ORR) is crucial for the commercialization of fuel cells and metal-air batteries. However, doped carbon-based materials only show good ORR activity in alkaline medium, and become less effective in acidic environment. We believe that an appropriate combination of both ionic and electronic transport path, and well dopant distribution of doped carbon-based materials would help to realize high ORR performance under both acidic and alkaline conditions. Accordingly, a nitrogen and sulfur co-doped carbon framework with hierarchical through-hole structure is fabricated by morphology-controlled solid-state pyrolysis of poly(aniline-co-2-aminothiophenol) foam. The uniform high concentrations of nitrogen and sulfur, high intrinsic conductivity, and integrated three dimensional ionic and electronic transfer passageways of the 3D porous structure lead to synergistic effects in catalyzing ORR. As a result, the limiting current density of the carbonized poly(aniline-co-2-aminothiophenol) foam is equivalent to commercial Pt/C in acidic environment, and twice the latter in alkaline medium.

Kinetics of electrochemical charge transfer in HT-PEM fuel cells

This paper presents experimental and modeling study of high temperature polymer electrolyte membrane fuel cell performance. The experiments are performed using in-house prepared MEA with an active area of 2.25 cm2. The experiments are simulated using a one dimensional distributed charge transfer model that resolves the properties along the thickness of the MEA. Six different HOR models and two different ORR models are subjected to initial studies. The model predictions are compared with cell performance on pure H2 and H2 with CO contamination. A detailed sensitivity analysis is carried out to understand the influence of various model parameters on cell performance over a range of potentials.

Type Iax supernovae as a few-parameter family

We present direct spectroscopic modeling of five Type Iax supernovae (SNe) with the one dimensional Monte Carlo radiative transfer code TARDIS. The abundance tomography technique is used to map the chemical structure and physical properties of the SN atmosphere. Through via fitting of multiple spectral epochs with self-consistent ejecta models, we can then constrain the location of some elements within the ejecta. The synthetic spectra of the best-fit models are able to reproduce the flux continuum and the main absorption features in the whole sample. We find that the mass fractions of IGEs and IMEs show a decreasing trend toward the outer regions of the atmospheres using density profiles similar to those of deflagration models in the literature. Oxygen is the only element, which could be dominant at higher velocities. The stratified abundance structure contradicts the well-mixed chemical profiles predicted by pure deflagration models. Based on the derived densities and abundances, a template model atmosphere is created for the SN Iax class and compared to the observed spectra. Free parameters are the scaling of the density profile, the velocity shift of the abundance template, and the peak luminosity. The results of this test support the idea that all SNe Iax can be described by a similar internal structure, which argues for a common origin of this class of explosions.

Detecting directional couplings from multivariate flows by the joint distance distribution.

The identification of directional couplings (or drive-response relationships) in the analysis of interacting nonlinear systems is an important piece of information to understand their dynamics. This task is especially challenging when the analyst's knowledge of the systems reduces virtually to time series of observations. Spurred by the success of Granger causality in econometrics, the study of cause-effect relationships (not to be confounded with statistical correlations) was extended to other fields, thus favoring the introduction of further tools such as transfer entropy. Currently, the research on old and new causality tools along with their pitfalls and applications in ever more general situations is going through a time of much activity. In this paper, we re-examine the method of the joint distance distribution to detect directional couplings between two multivariate flows. This method is based on the forced Takens theorem, and, more specifically, it exploits the existence of a continuous mapping from the reconstructed attractor of the response system to the reconstructed attractor of the driving system, an approach that is increasingly drawing the attention of the data analysts. The numerical results with Lorenz and Rössler oscillators in three different interaction networks (including hidden common drivers) are quite satisfactory, except when phase synchronization sets in. They also show that the method of the joint distance distribution outperforms the lowest dimensional transfer entropy in the cases considered. The robustness of the results to the sampling interval, time series length, observational noise, and metric is analyzed too.

Polarization as a probe of dusty environments around Type Ia supernovae: radiative transfer models for SN 2012dn

Geometry of circumstellar (CS) medium around supernovae (SNe) provides important diagnostics to understand the nature of their progenitors. In this paper, properties of CS dust around SN 2012dn, a super-Chandrasekhar candidate Type Ia supernova (SC-SN), have been studied through detailed three dimensional radiation transfer simulations. With the detected near-infrared excess from SN 2012dn, we show that it has a disk-like dusty CS environment whose mass is roughly consistent with a branch of an accreting white dwarf system (the single degenerate scenario). We show that a similar system should produce polarization signals up to $\sim 8$ \% in the $B$ band, depending on the viewing direction if polarimetric observation is performed. We predict that the maximum polarization is reached around $\sim 60$ days after the $B$-band maximum. We show that the temporal and wavelength dependence of the polarization signals, together with other unique features, can be easily distinguished from the interstellar polarization and intrinsic SN polarization. Indeed, the small polarization degree observed for normal Type Ia SNe (SNe Ia) can constrain a parameter space in the CS dust mass and distribution. We thus encourage multi-band polarimetric observations for SNe Ia, especially for outliers including SC-SNe for which some arguments for the single degenerate scenario exist but the polarization data are very rare so far.